The prior art abounds with strap-on orthotic knee devices to be worn by persons recuperating from surgery or injuries to the knees. Most of the prior art devices include a strap-on thigh engaging section and a strap-on leg engaging section connected by a pair of tang in clevis joints which permit the user the freedom to extend and bend the knee over a full range. One currently available strap-on orthotic knee device incorporates tang in clevis joints with automatically engaging locking devices which snap in at full extension of the knee joint and requires the manual disengagement of the locking device by means of a finger loop to allow bending of the joint.
The prior art strap-on orthotic knee device with the automatically engaging locking device has two major drawbacks or disadvantages. The first drawback or disadvantage is due to the fact that the locking, while automatic, can occur only when the user has achieved full extension of the knee. This creates a safety hazard and causes accidents in that the user may not be able to fully extend the knee before loading (placing weight on) the leg, which could cause the knee to fold uncontrollably, and permit the user to fall. The second drawback or disadvantage relates to the manual operation required to disengage or unlock the joint, which operation is cumbersome in that the user must have a free hand to devote to the control loop and could discourage the user from the therapeutic bending of the knee.
The present invention overcomes the disadvantages, drawbacks or deficiencies of the prior art devices in that it provides a rapid, automatic, locking and unlocking of the joint according to the load being carried by the joint. The joint of the present invention automatically locks when weight is applied thereto, even when the knee is slightly bent, thus allowing the joint to remain free to rotate when unloaded, to permit more freedom of motion and mobility to the user. The rapid, automatic, loading and unloading of the joint prevents accidents and encourages the user to exercise the knee to rehabilitate same.
Accordingly, it is an object of the present invention to provide a new and improved tang in clevis joint for strap-on orthotic knee devices which incorporates locking and unlocking structure which is rapid and automatic in operation and prevents the unwanted folding of the joint.
It is a further object of the present invention to provide a rapid and automatic locking and unlocking tang in clevis joint for strap-on orthotic knee devices which prevents accidents, encourage exercise by the user, and aids in the rehabilitation of the injured knee.
It is still a further object of the present invention to provide a tang in clevis joint for strap-on orthotic knee devices which automatically locks and unlocks the knee to allow the free rotation of the knee and the locking of the knee as desired.
Other aspects, objects and advantages of this invention will become apparent to those skilled in the art to which this invention pertains from a study of the preferred embodiment as set forth in the specifications, drawings and the appended claims.